Zombie planet returns from the dead

A recently published study suggests that a planet some astronomers believed didn't exist, does in fact, live. The study leans on observations made using the Hubble Space Telescope of a bright star called Fomalhaut. The observations made using the Hubble suggests that the star does indeed have a massive exoplanet orbiting it.

There has been a suggestion the scientific community made by other studies that the exoplanet dubbed Fomalhaut b is actually nothing but a giant dust cloud. One of the co-authors of the new study, John Debes, says that he and his team believe they're seeing a planetary object that is completely embedded in dust rather than a free-floating dust cloud. Discussions on whether or not the star had a dust cloud or a large planet orbiting it began in 2008.

In November 2008, astronomers announced that a planet circled Fomalhaut, which is a bright star 25 light-years away situated in the constellation Piscis Austrinus. The exoplanet was a big deal in 2008 because it was the first alien world to be directly imaged in visible light. The planet was spotted in a vast debris ring surrounding the star, but slightly offset.

Other scientists argued against the possibility of a planet orbiting the star saying that the object discovered was a short-lived dust cloud. These opponents to the existence of Fomalhaut b cited the brightness variations reported by the discovery team and back that up with the fact that the NASA Spitzer Space Telescope was unable to pick up the infrared signature of the planet. The new study reports that the researchers have spotted the exoplanet in three different wavelengths of visible light by reanalyzing Hubble data from 2004 and 2006. The new study team also claims that the orbital characteristics of the planet and its gravity could be shaping the debris disk surrounding the star.

"What we've seen from our analysis is that the object's minimum distance from the disk has hardly changed at all in two years, which is a good sign that it's in a nice ring-sculpting orbit," said co-author Timothy Rodigas of the University of Arizona.